抄録
The dependence of α-Fe particle size on the formation of Fe16N2 with giant magnetization was studied by nitriding α-Fe fine particles below 200°C with different particle size (60nm, 120nm, 300nm) derived from α-Fe2O3. Nitridation of the largest α-Fe particle (300nm) was difficult to obtain Fe16N2. Mixtures of Fe16N2 with unreacted α-Fe and Fe4N were obtained by nitridation of the smaller α-Fe particles (120nm, 60nm). The nitridation process was most controllable for α-Fe particle of 120nm to obtain the most amount of Fe16N2. Magnetization was not enhanced by the formation of Fe16N2 probably due to disordering of the nitrogen introduced into Fe lattice. Monodispersed α-Fe particles could be obtained by thermal decomposition of Fe(CO)5 in octylether. Their size could be controlled with the amount of added stabilizer in the ether. They could be nitrided to Fe16N2 in low temperature nitridation.
